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Walter Weder

Publications and source records attributed to Walter Weder.

43 records · Page 3Linked to original sources
PubMed2002

Patient selection for lung volume reduction surgery: is outcome predictable?

Patient selection for lung volume reduction surgery (LVRS) relies on sound physiologic concepts and experience from large case series. LVRS should be considered in severely symptomatic emphysema with marked airflow obstruction and hyperinflation despite optimal medical management, and in the absence of major comorbidities associated with excessive perioperative risks. Qualitative estimation of functional benefit from LVRS in suitable candidates has been based on functional criteria (e.g., high inspiratory conductance, high residual volume/total lung capacity ratio), on heterogeneity of emphysema assessed by computed tomography (CT) or perfusion scans, and on severity of emphysema assessed by CT or impaired diffusing capacity. Selection strategies relying on such criteria have provided favorable functional results at a low mortality, but further validation of potential outcome predictors in prospective trials is needed.

Adult↗
PubMed2002

Gain and subsequent loss of lung function after lung volume reduction surgery in cases of severe emphysema with different morphologic patterns.

OBJECTIVE: Surgical lung volume reduction improves lung function and dyspnea in advanced emphysema to a variable degree. Because long-term results with this procedure are scant, we prospectively investigated lung function over several years after lung volume reduction surgery with regard to emphysema morphology. METHODS: Bilateral video-assisted thoracoscopic lung volume reduction surgery was performed in severely symptomatic patients with marked hyperinflation caused by advanced nonbullous emphysema. Emphysema heterogeneity was visually graded on chest computed tomography. Symptoms and lung function were assessed before the operation and 3, 6, and then every 6 months after the operation. RESULTS: A total of 115 patients with a median forced expiratory volume in 1 second of 0.73 L (27% of predicted value) underwent lung volume reduction surgery. Follow-up extended over a median of 37 months. Median forced expiratory volume in 1 second significantly increased within 6 months after the operation by 37% in homogeneous (n = 27), by 38% in intermediately heterogeneous (n = 37), and by 63% in markedly heterogeneous emphysema (n = 51, P <.05 vs. other morphologies). Maximal forced expiratory volume in 1 second was reached within 6 months after lung volume reduction surgery and decreased in the first postoperative year by 0.16 L per year in homogeneous, by 0.19 L per year in intermediately heterogenous, and by 0.32 L per year in markedly heterogeneous emphysema (P <.01 vs. other morphologies). The decline in forced expiratory volume in 1 second over subsequent years decelerated according to an exponential decay and was similar for all morphologic types (median annual decrease of 0.09 L [9%]). CONCLUSIONS: Lung volume reduction surgery improves lung function in severe homogeneous and, to an even greater extent, heterogeneous emphysema. Forced expiratory volume in 1 second peaks within 6 months postoperatively. The subsequent decline is most rapid in the first year and slows down in succeeding years according to an exponential decay. Therefore, long-term functional results of lung volume reduction surgery may be more favorable than expected from linear extrapolations of short-term observations.

Adult↗
PubMed2002

Successful lung volume reduction surgery in a child with severe airflow obstruction and hyperinflation due to constrictive bronchiolitis.

Lung volume reduction surgery (LVRS) may improve pulmonary function in patients with severe emphysema. However, its effects in other types of obstructive lung disease are unknown. To delay the need for lung transplantation, we performed LVRS in a 14-year-old boy with disabling airflow obstruction/hyperinflation secondary to postinfectious bronchiolitis nonresponsive to medical therapy. Within days after LVRS, a major improvement of symptoms and lung function occurred and persisted for > 1 year. Our observation suggests that LVRS may be a novel treatment option in selected patients with extreme hyperinflation even if the underlying disease is not emphysema.

Adolescent↗
PubMedDate not supplied

Acute amiodarone-induced pulmonary toxicity following lung resection.

Amiodarone-induced pulmonary toxicity has been described mostly in patients receiving large doses of the drug over prolonged periods. In this report, we describe the early onset of acute pulmonary toxicity leading to acute respiratory distress syndrome after a short course of amiodarone treatment following middle-lobe non-small-cell lung cancer resection.

Aged↗
PubMedDate not supplied

Model-based versus clinical prediction of the spirometric response to lung volume reduction surgery.

BACKGROUND: Lung volume reduction surgery (LVRS) improves symptoms and lung function in selected patients with severe emphysema. OBJECTIVES: We investigated whether models based on physiologic and radiologic predictors discriminated patients with a favorable from those with a poor spirometric response to LVRS. METHODS: Data of a derivation cohort of 70 patients who had previously undergone LVRS served to develop two types of prediction models, lookup functions and logistic regression equations. Presence or absence of improvement in forced expiratory volume in 1 s (FEV1) > or =300 ml and forced vital capacity (FVC) > or =500 ml represented dichotomous outcomes. The residual volume/total lung capacity ratio, CT-radiological emphysema heterogeneity scores and diffusing capacity, a marker of emphysema severity, were the predictors. Models were used to predict spirometric outcomes for a validation cohort of 60 emphysema patients referred for LVRS. Furthermore, the surgeon preoperatively estimated outcomes based on all available clinical data but blinded to model predictions. Spirometric changes within 6 months following surgery were compared to predictions. RESULTS: Median FEV1 in the validation cohort increased from 0.69 to 1.00 liters (+41%), and FVC from 2.07 to 2.78 liters (+29%; p < 0.05 for changes). Lookup functions and logistic regression equations identified patients experiencing major increases in FEV1 > or =300 ml and FVC > or =500 ml with an accuracy quantified by areas under the receiver-operating characteristic curves of 0.72 to 0.76 (all areas >0.5, p < 0.05). Predictions by the surgeon had an accuracy of 0.71 to 0.78 (p = NS vs. models). CONCLUSIONS: The accuracy of models based on three predictors was fair and similar to assessment by an experienced surgeon based on all available clinical information. Prediction models may contribute to the consistent assessment of LVRS candidates.

Humans↗